Benign or Malignant Brain Cancers
- Benign brain tumors do not contain cancer cells:
- Usually, benign tumors can be removed, and they seldom grow back.
- Benign brain tumors usually have an obvious border or edge. Cells from benign tumors rarely invade tissues around them. They don’t spread to other parts of the body. However, benign tumors can press on sensitive areas of the brain and cause serious health problems.
- Unlike benign tumors in most other parts of the body, benign brain tumors are sometimes life threatening.
- Benign brain tumors may become malignant.
- Malignant brain tumors (also called brain cancer) contain cancer cells:
- Malignant brain tumors are generally more serious and often are a threat to life.
- They are likely to grow rapidly and crowd or invade the nearby healthy brain tissue.
- Cancer cells may break away from malignant brain tumors and spread to other parts of the brain or to the spinal cord. They rarely spread to other parts of the body.
Doctors group brain tumors by grade
. The grade of a tumor refers to the way the cells look under a microscope:
- Grade I: The tissue is benign. The cells look nearly like normal brain cells, and they grow slowly.
- Grade II: The tissue is malignant. The cells look less like normal cells than do the cells in a Grade I tumor.
- Grade III: The malignant tissue has cells that look very different from normal cells. The abnormal cells are actively growing (anaplastic).
- Grade IV: The malignant tissue has cells that look most abnormal and tend to grow quickly.
Cells from low-grade tumors (grades I and II) look more normal and generally grow more slowly than cells from high-grade tumors (grades III and IV).
Over time, a low-grade tumor may become a highgrade tumor. However, the change to a high-grade tumor happens more often among adults than children.
Types of Primary Brain Tumors
There are many types of primary brain tumors. Primary brain tumors are named according to the type of cells or the part of the brain in which they begin. For example, most primary brain tumors begin in glial cells. This type of tumor is called a glioma
Among adults, the most common types are:
- Astrocytoma: The tumor arises from star-shaped glial cells called astrocytes. It can be any grade. In adults, an astrocytoma most often arises in the cerebrum.
- Grade I or II astrocytoma: It may be called a low-grade glioma.
- Grade III astrocytoma: It’s sometimes called a high-grade or an anaplastic astrocytoma.
- Grade IV astrocytoma: It may be called a glioblastoma or malignant astrocytic glioma.
- Meningioma: The tumor arises in the meninges. It can be grade I, II, or III. It’s usually benign (grade I) and grows slowly.
- Oligodendroglioma: The tumor arises from cells that make the fatty substance that covers and protects nerves. It usually occurs in the cerebrum. It’s most common in middle-aged adults. It can be grade II or III.
Among children, the most common types are:
- Medulloblastoma: The tumor usually arises in the cerebellum. It’s sometimes called a primitive neuroectodermal tumor. It is grade IV.
- Grade I or II astrocytoma: In children, this lowgrade tumor occurs anywhere in the brain. The most common astrocytoma among children is juvenile pilocytic astrocytoma. It’s grade I.
- Ependymoma: The tumor arises from cells that line the ventricles or the central canal of the spinal cord. It’s most commonly found in children and young adults. It can be grade I, II, or III.
- Brain stem glioma: The tumor occurs in the lowest part of the brain. It can be a low-grade or high-grade tumor. The most common type is diffuse intrinsic pontine glioma .
Types of Treatment
People with brain tumors have several treatment options. The options are surgery
, radiation therapy
. Many people get a combination of treatments.
The choice of treatment depends mainly on the following:
- The type and grade of brain tumor
- Its location in the brain
- Its size
- Your age and general health
For some types of brain cancer, the doctor also needs to know whether cancer cells were found in the cerebrospinal fluid.
Your doctor can describe your treatment choices, the expected results, and the possible side effects
. Because cancer therapy often damages healthy cells and tissues, side effects are common. Before treatment starts, ask your health care team about possible side effects and how treatment may change your normal activities. You and your health care team can work together to develop a treatment plan that meets your medical and personal needs.
You may want to talk with your doctor about taking part in a clinical trial
, a research study of new treatment methods. See the Taking Part in Cancer Research
Your doctor may refer you to a specialist, or you may ask for a referral. Specialists who treat brain tumors include neurologists
, medical oncologists
, radiation oncologists
, and neuroradiologists
Your health care team may also include an oncology nurse
, a registered dietitian
, a mental health counselor
, a social worker
, a physical therapist
, an occupational therapist
, a speech therapist
, and aphysical medicine specialist
. Also, children may need tutors to help with schoolwork. (The Rehabilitation
section has more information about therapists and tutors.)
Surgery is the usual first treatment for most brain tumors. Before surgery begins, you may be given general anesthesia, and your scalp is shaved. You probably won’t need your entire head shaved.
Surgery to open the skull is called a craniotomy
. The surgeon makes an incision in your scalp and uses a special type of saw to remove a piece of bone from the skull.
You may be awake when the surgeon removes part or all of the brain tumor. The surgeon removes as much tumor as possible. You may be asked to move a leg, count, say the alphabet, or tell a story. Your ability to follow these commands helps the surgeon protect important parts of the brain.
After the tumor is removed, the surgeon covers the opening in the skull with the piece of bone or with a piece of metal or fabric. The surgeon then closes the incision in the scalp.
Sometimes surgery isn’t possible. If the tumor is in the brain stem or certain other areas, the surgeon may not be able to remove the tumor without harming normal brain tissue. People who can’t have surgery may receive radiation therapy or other treatment.
You may have a headache or be uncomfortable for the first few days after surgery. However, medicine can usually control pain. Before surgery, you should discuss the plan for pain relief with your health care team. After surgery, your team can adjust the plan if you need more relief.
You may also feel tired or weak. The time it takes to heal after surgery is different for everyone. You will probably spend a few days in the hospital.
Other, less common problems may occur after surgery for a brain tumor. The brain may swell or fluid may build up within the skull. The health care team will monitor you for signs of swelling or fluid buildup. You may receive steroids
to help relieve swelling. A second surgery may be needed to drain the fluid. The surgeon may place a long, thin tube (shunt
) in a ventricle of the brain. (For some people, the shunt is placed before performing surgery on the brain tumor.) The tube is threaded under the skin to another part of the body, usually the abdomen. Excess fluid is carried from the brain and drained into the abdomen. Sometimes the fluid is drained into the heart instead.
Infection is another problem that may develop after surgery. If this happens, the health care team will give you an antibiotic
Brain surgery may harm normal tissue. Brain damage can be a serious problem. It can cause problems with thinking, seeing, or speaking. It can also cause personality changes or seizures. Most of these problems lessen or disappear with time. But sometimes damage to the brain is permanent. You may need physical therapy, speech therapy, or occupational therapy.
Radiation therapy kills brain tumor cells with high-energy x-rays
, gamma rays
, or protons
Radiation therapy usually follows surgery. The radiation kills tumor cells that may remain in the area. Sometimes, people who can’t have surgery have radiation therapy instead.
Doctors use external and internal types of radiation therapy to treat brain tumors:
- External radiation therapy: You’ll go to a hospital or clinic for treatment. A large machine outside the body aims beams of radiation at the head. Because cancer cells may invade normal tissue around a tumor, the radiation may be aimed at the tumor and nearby brain tissue, or at the entire brain. Some people need radiation aimed at the spinal cord also. The treatment schedule depends on your age, and the type and size of the tumor. Fractionated external beam therapy is the most common method of radiation therapy used for people with brain tumors. Giving the total dose of radiation over several weeks helps to protect healthy tissue in the area of the tumor. Treatments are usually 5 days a week for several weeks. A typical visit lasts less than an hour, and each treatment takes only a few minutes. Some treatment centers are studying other ways of delivering external beam radiation therapy:
- Internal radiation therapy (implant radiation therapy or brachytherapy): Internal radiation isn’t commonly used for treating brain tumors and is under study. The radiation comes from radioactivematerial usually contained in very small implants called seeds. The seeds are placed inside the brain and give off radiation for months. They don’t need to be removed once the radiation is gone.
Some people have no or few side effects after treatment. Rarely, people may have nausea for several hours after external radiation therapy. The health care team can suggest ways to help you cope with this problem. Radiation therapy also may cause you to become very tired with each radiation treatment. Resting is important, but doctors usually advise people to try to stay as active as they can.
Also, external radiation therapy commonly causes hair loss from the part of the head that was treated. Hair usually grows back within a few months. Radiation therapy also may make the skin on the scalp and ears red, dry, and tender. The health care team can suggest ways to relieve these problems.
Sometimes radiation therapy causes brain tissue to swell. You may get a headache or feel pressure. The health care team watches for signs of this problem. They can provide medicine to reduce the discomfort. Radiation sometimes kills healthy brain tissue. Although rare, this side effect can cause headaches, seizures, or even death.
Radiation may harm the pituitary gland
and other areas of the brain. For children, this damage could cause learning problems or slow down growth and development. In addition, radiation increases the risk of secondary tumors later in life.
Chemotherapy, the use of drugs to kill cancer cells, is sometimes used to treat brain tumors. Drugs may be given in the following ways:
- By mouth or vein (intravenous): Chemotherapy may be given during and after radiation therapy. The drugs enter the bloodstream and travel throughout the body. They may be given in an outpatient part of the hospital, at the doctor’s office, or at home. Rarely, you may need to stay in the hospital. The side effects of chemotherapy depend mainly on which drugs are given and how much. Common side effects include nausea and vomiting, loss of appetite, headache, fever and chills, and weakness. If the drugs lower the levels of healthy blood cells, you’re more likely to get infections, bruise or bleed easily, and feel very weak and tired. Your health care team will check for low levels of blood cells. Some side effects may be relieved with medicine.
- In wafers that are put into the brain: For some adults with high-grade glioma, the surgeon implants several wafers into the brain. Each wafer is about the size of a dime. Over several weeks, the wafers dissolve, releasing the drug into the brain. The drug kills cancer cells. It may help prevent the tumor from returning in the brain after surgery to remove the tumor. People who receive an implant (a wafer) that contains a drug are monitored by the health care team for signs of infection after surgery. An infection can be treated with an antibiotic.
Information from National Cancer Institute.